SUMMARY: Our investigation focuses upon the elaboration of subcellular membranes during cytodifferentiation of the exocrine rat pancreas. We will continue our studies of glycosyltransferases and glycosyltransferases and glycoprotein synthesis, as well as sulfated glycosaminoaglycans. A second aspect of the project is to define the biochemical changes in the cell surface using plant lectins and surface specific reagents as probes.